The standard height and weight of a 9-week-old boy is usually around 126.5-137.8cm and 24.3-34kg, but there are individual differences. Standard height and weight can generally be used as a reference, 9-week-old boy’s height is 126.5-137.8cm and weight is around 24.3-34kg, which are usually within the normal range. However, a child’s height and weight are very much related to parental genetics, as well as diet, sleep, exercise, etc. Individual differences are large, and some will be slightly above the normal range, while others slightly below, but the child’s diet, sleep, and mental health are all good, are generally normal. Although there is no absolute standard, but if the height and weight of a 9-year-old boy is significantly different from that of a child of the same age, it is recommended to consult a doctor in a timely manner to exclude disease factors, and if necessary, active treatment and treatment.